(a) I'm skeptical that the US has actually banished "the overt trappings of systemic, institutional racism", given, say, the asymmetries of police brutality, the evisceration of the Voting Rights Act, or the extent to which a non-trivial white nationalist constituency contributed to the election of the current President—just to name a few examples. Unless you think "chattel slavery" is the only manifestation of "overt trappings of systemic, institutional racism" this nation has to reckon with.
(b) I actually think it's an apt metaphor how far is left to go, despite real material progress, and how easy it is to slide into trite, solipsistic complacency on the topic. "I mean, we took out the bad verse, didn't we? What more do they want?"
(c) [And this is the take.] It's a ****ty poem. Its stupid jingoism is only matched by the banality of its sentiment and the heavy-handed obviousness of its language. It also explicitly frames patriotism and national pride as martial, codifying that attachment for many Americans. Wilson was mistaken to render it official, and Congress was mistaken to later confirm that decision. Not only that, but the song from which the poem took its music—The Anacreontic Song—is better-written, even if less-known.